Sinclair & the Pocket Calculator Clive Sinclair and the Pocket calculator © 2003 Nigel Tout This is a new article which was not originally in "The International Calculator Collector". The Sinclair Exectuive For people in Britain in the 1970s and 1980s Clive Sinclair was known as "the inventor of the pocket calculator". Although not really true (it depends on how big your pocket is), Sinclair stunned the world in the summer of 1972 when he launched his first electronic calculator, the Executive, which was smaller and considerably thinner than any other on the market. The vital statistics of the Sinclair Executive are 56mm x 138mm x 9mm / 2.2" x 5.4" x 0.35" and it fits easily into a shirt pocket without making a bulge. The first Sinclair calculator, the Executive. The memory version, the Executive Memory. Side view showing how thin the executive models are. Clive Sinclair is an electronics genius and is noted for his miniature products achived by using very innovative designs. The Executive uses one of the standard calculator chips of the time, the Texas Instruments GLS 1802.

This normally has a current consumption of about 300 mA which dictates that normal AA size batteries, or larger, need to be used to give a decent battery life. Sinclair in his quest for miniturisation, to produce a true pocket calculator, wanted to use button cells rather than normal batteries, but these would be drained in minutes by the chip and the LED display. However, Chris Curry and JimWestwood at Sinclair Radionics, in Huntingdon, England, found that the power to the chip did not have to be on continuously, it could be pulsed and the internal capacitance of the chip would store enough electrical charge to keep it working till the next power pulse. Power pulses lasting 1.7 microseconds are used, at a frequency of 200 KHz during calculations and 15KHz between each operation, reducing the power consumption to 25 to 30 mW. Texas Instruments did not recommend operating in this way, but it allows the Executive to get about 20 hours continuous operation from 3 small mercury button cells. The unusual, Sinclair designed keyboard also contributes to the small size of the Executive, with the little rubber pips which press directly on the beryllium-copper contacts.

Early days Born in 1940, Clive became intensely interested in mathematics and electronics at school, and designed his own electronic circuits. While at school he wrote his first article for the magazine Practical Wireless which was published, and he went for holiday jobs in electronic companies. Clive left school just before his eighteenth birthday. Although he could have gone to university, he did not, reckoning that he could find out anything that he wanted to know by himself. Clive's father was a business man, and Clive showed the same business flair. While at school he had drawn up details in an exercise book of the Sinclair Micro Radio Kit, complete with costings to the last detail, including postage and packing. He realised that electronic components were very cheap if bought in thousands, and that large advertisements in the hobby electronics magazines would be eye-catching and bring in orders. Fortunately, the magazine Practical Wireless advertised for an editorial assistant, which Clive applied for and got. Shortly afterwards, in 1958, Bernard Babani enticed Clive away to run his technical publishing company, where Clive also wrote thirteen contructor's books by 1962.

Clive still had ambitions to form his own company, and had registered the company Sinclair Radionics in 1961. Having found financial backing he left Babani's, only to have the backer get cold feet and withdraw. Clive then got a job as technical editor with the journal Instrument Practice, for which he also wrote articles. One of his tasks was to produce a comprehensive survey of the available semiconductors, which opened the door for him at all the semiconductor manufacturers. At one of the manufacturers, Clive discoverd that there were tens of thousands of transistors available very cheaply because they were outside the manufacturer's published specification. However, this did not make them useless, so Clive bought them up, tested them, re-named them, and sold them together with designs for their use. In late 1962 the first advertisements from Sinclair Radionics for a Micro-amplifier kit appeared. The Sinclair Radionics office, with research, development, and marketing, was in Cambridge, with the kits being produced and despatched nearby by Cambridge Consultants Ltd., a contract research and development company.

The Micro-amplifier was followed by the Sinclair Slimline micro radio, the smallest radio on the market at 2.75" x 1.625" x 0.625" (70 x 41 x 16 mm). This was to be the pattern of Sinclair's electronics business. The products were miniaturised and highly innovative; the advertisements for them were large and eye-catching; they were sold by mail order, generally as kits; and they were competitively priced. Unfortunately, the down side to this business model was soon discovered. If a new product was very attractive, so many orders were received that production was overwhelmed and there were long delays in sending them out. This was to be a recurring problem for Sinclair, as also was poor quality control in the rush to meet orders. To mitigate this was the Sinclair policy of exchanging faulty items immediately with no questions asked. Sinclair Radionics followed up with further very innovative amplifiers, micro radios, and hi-fi units for the hobbyist, which were sold through stores as well as by mail order. Another innovation, "Sinclair News" started to be produced in 1964, with information about Sinclair Radionics and its products.

Sinclair Radionics was very successful, and in 1970, due to the needs for space, moved into part of an old flour mill in St. Ives, then in Huntingdonshire, alongside another electronics company. Calculators In 1972 the Sinclair moved into pocket calculators with the Executive, as outlined above, and also the first Sinclair portable digital multimeter was launched. Sinclair had shown what could be done with miniaturising calculators, and the competition would soon start to follow, so he had to keep an innovative lead. The Cambridge series of calculators followed the Executive, with the first model being launched in 1973. The first of the Sinclair Cambridge range. The Sinclair Cambridge range were all based on the same small, pleasingly rounded shape which could easily fit in the pocket. Most used AAA pen cell batteries, but some later models were spoilt be requiring a thick 9v PP3 battery, which required a "pregnant" bulge on the back. The Sinclair business philosophy was to research and design its products itself but to sub-contract manufacture. In this way it could respond quickly to market changes.

However, this makes modification of the design tricky and quality control more difficult, which caused problems with the thousands of calculators now being exported, and being sold to non-hobbyists. In 1973, Sinclair set up its first quality control department to address this problem. Following on from the ingenious use of an exisiting calculator chip in the Executive, to minimise power consumption, Sinclair managed to produce a scientific calculator using a cheap non-scientific calculator chip. The first hand-held scientific calculator, the Hewlett Packard HP-35 , had been launched in early 1972, but was expensive, and Clive wanted to compete with this. Calculator chips have the possibility of having their operating instructions altered by using different masks in the manufacturing process. Nigel Searle, at Sinclair Radionics, managed to implement scientific algorithms on a standard Texas Instruments chip to give a low-cost scientific calculator, though with a lower specification than the HP-35. The Sinclair Scientific low cost scientific calculator. The Scientific provides the basic trigonometric functions and log/antilog. It uses Reverse Polish Notation (RPN) like the HP-35, and gives results in scientific notation.

Like many Sinclair calculators it was available even cheaper as a self assembly kit. In 1974 Sinclair produced a design for Gillette, since the shaver manufacturer had decided to diversify into consumer electronics. The result was the Gillette GPA calculator, which was sold for a short period before Gillette reversed its decision on moving into calculators. Sinclair used the Gillette GPA as the basis for its Oxford range, launched in 1975. Gillette GPA. Sinclair Oxford 100. The Sinclair Oxford range comprised several models, with the early ones having LED displays. Later a change was made to the lower power consumption green VFDs (Vacuum Fluorescent Displays), and the case was made more rounded. Earlier Sinclair Oxford 200 with red LED display, and later version with green VFD (Vacuum Fluorescent Display). The pocket calculator had been a great success for Sinclair, but by the late 1970s it was starting to feel the effects of small, cheap, highly reliable calculators from Japan.

Sinclair had also decided to stick with LED and VFD displays, whereas Japanese manufacturers were starting to shift to LCDs (Liquid Crystal Displays), which had very low power consumption and batteries lasted for months. Sinclair produced a few more models, including the cheap programmable Enterprise Programmable. Like all the Sinclair programmable models, it was provided with comprehensive manuals with sample programs in different subjects. Sinclair Enterprise Programmable and programming manuals. The elegant Sinclair Sovereign, Designed by John Pemberton, received a major design award and was a move upmarket. Available in black and polished chrome, a gold finish version was produced, and to commemorate the Silver Jubilee (25 years) of the reign of Queen Elizabeth II in 1977 there was a limited edition silver plated version. Limited edition "silver jubilee" Sinclair Sovereign. Miniature TVs, troubles, computers While all the developments with the calculators had been taking place a lot of other things had been happening at Sinclair Radionics. With his interest in miniaturising electronics it was natural that Clive would look into developing a miniature television. This had started in the early 1960s and a Microvision was exhibited in 1966.

However, the problems were enormous - finding a source of small TV tubes; the high power consumption; the high voltages; the complexity - and it never went into production. The pursuit of the dream of the hand-held television was to consume an awful lot of time, effort, and money at Sinclair Radionics. It was not until ten years later, in 1976, that the Sinclair TV1A Microvision was launched. Although only a black & white model, it was revolutionary in being the first multi-standard receiver, worked on VHF and UHF, and so could be used around the world. Clive's ultimate idea was a flat screen TV and work continued on devolping a near flat television tube. The cost of developing the TV had been very high and the calculator business was now unprofitable. There were high hopes of the Sinclair Black Watch, an LED digital watch in a futuristic black plastic casing. But there were problems with the semiconductor manufacturers and the company producing the plastic mouldings, resulting in it being about two years late. By this time digital watches were starting to use LCDs which display continuously, and there were major quality and battery life problems, so the Black Watch flopped.

Clive Sinclair had a deserved reputation of being a very innovative entrepreneur, but by the end of 1976 Sinclair Radionics was in financial difficulties. The British government's National Enterprise Board (NEB) bought heavily into Sinclair Radionics, and was especially interested in the flat screen television which might rejuvenate the ailing UK television industry. However, the financial situation got no better. The NEB gave further heavy financial help but was under pressure not to lose the taxpayer's money, so they tried to raise money by selling off assets. The calculators were no longer profitable, so in 1979 the rights to the Radionics name, together with parts and dies, were sold to the ESL Bristol group of companies under the name Radionics Products Ltd. The NEB also sold the television business to Binatone, but retained the Sinclair instruments division which was later taken over and became Thandar. While Sinclair Radionics was collapsing under the NEB, Chris Curry and Clive Sinclair had been discussing alternatives which resulted in them starting another company, Sinclair Instruments Ltd. It launched its first product, the Sinclair Wrist Calculator, which made use of redundant electronics components, and changed its name to Science of Cambridge.

Sinclair Wrist Calculator. Although the Wrist Calculator sold reasonably well it had the old Sinclair problem of poor quality control. The wrist calculator was the last of the line of calculators that were developed under Clive Sinclair. The dates of introduction of some of his notable calculator models are listed below. All are from Sinclair Radionics Ltd., except where noted[2]: June 1972 - Sinclair Executive - there are two versions of the Executive. August 1973 - the first Cambridge model. There are nearly a dozen Cambridge models, ranging from simple 4-function machines to the Cambridge Programmable. November 1973 - Sinclair Executive Memory. April 1974 - Sinclair Scientific. This used the casing of the Cambridge models. March 1975 - Sinclair Oxford models. Initially there were 3 models, the 100, 200, and 300 with LED displays. Later versions had VFD displays, and other Oxford models followed. August 1975 - Sinclair Scientific Programmable. Late-1976 - Sinclair Sovereign model. February 1977 - Sinclair Cambridge Scientific.

February 1977 - Sinclair Wrist Calculator (from Sinclair Instruments Ltd.). October 1977 - Sinclair Enterprise. February 1978 - Sinclair President. July 1978 - Sinclair Enterprise Programmable. Fortunately, microprocessors were now becoming common items, and Chris Curry remembered that Ian Williamson, a young electronics engineer, had produced a design for a microprocessor hobbyists kit. Although Clive was not very enthusiastic, this was developed further, and sold as the Science of Cambridge MK14 (Microcomputer Kit 14), though comprising of little more than circuit board with electronics, 8-digit LED display, calculator type keyboard, and instructions of how to use it. However, Chris Curry was fed up with Clive and his lack of enthusiasm for the MK14, so he left Science of Cambridge, and started up Acorn Computers to develop the MK14 concept further. At this time developments in microprocessors, "the computer on a chip", were newsworthy and the MK 14 sold well to those wanting to find out more.

Clive realised the potential, and developments continued, soon leading to the Sinclair ZX80, the world's smallest and cheapest computer, being launched in 1980. The ZX80 was highly successful, and was followed by a series of improved models. However, the old Sinclair problems of being unable to meet high demand and quality control took their toll, especially with the Sinclair QL. In 1984 Sinclair finally launched a flat screen TV which was moderately successful, but by now there were competitors around in the hand-held TV market. The Sinclair flat-screen pocket-sized television which cost such a lot to develop. The screen is actually a cathode ray tube with the electron beam coming from the side. Sinclair's last high-profile product was the C5 electric tricycle, launched in 1985. This was a valiant design for a very environmetally friendly, low-slung, streamlined, electric vehicle. However, it was not very practical in traffic and sales were poor before it was discontinued. Since then, Sir Clive, as he was honoured, has maintained a low profile, and sadly very little has appeared under the Sinclair name.

Sinclair products have a good following among collectors, where the innovative designs which make them stand out from the rest are greatly appreciated. For further information about Sinclair calculators and more photographs see the Sinclair Calculators section on this site. Sources of information: Dale, R., (1985), "The Sinclair Story", London, Duckworth, ISBN 0 7156 1901 2. Adamson, I., and Kennedy, R., (1996) "Sinclair and the 'Sunrise' Technology", Harmondsworth, Penguin Books Ltd., ISBN 0-14-008774-5. "Electronics" magazine. INVENTOR - TRYING AGAIN IN CONSUMER ELECTRONICS - NYTimes.com INVENTOR; TRYING AGAIN IN CONSUMER ELECTRONICS By ELIZABETH BAILEY Published: April 12, 1981 LONDON The British, it is said, are great at designing a product but awful at exploiting it. In earlier eras, for example, much of the original work on the jet engine, the computer, radar and the early work on semiconductors was done in Britain.

But the money on them was made elsewhere. Clive Sinclair seems living proof that the axiom holds true today. In 1972, his Sinclair Radionics came out with the Executive, in a neck-and-neck race with Texas Instruments to market the world's first hand-held calculator. The Government poured millions into the venture. But it was swept away by a tide of cheaper, more sophisticated American and Japanese models. An economic artifact, the calculator now sits in the design gallery of New York's Museum of Modern Art. ''The message has come through loud and clear that Sinclair is a good designer, but he is no good at running a business,'' said Richard Harwood, a financial analyst with the London-based brokerage firm Scott, Goff, Hancock & Company. That may be rather too hasty a judgment. Mr. Sinclair is back, as head of Sinclair Research, maker of a highly successful line of microcomputers -and now he has what he hopes will be truly a first. It's pocket-sized television, a 6-by-4-by-1-inch black-and-white model that weighs only a few ounces. Again, he has Government support. And this time, Mr. Sinclair vows he is not going to repeat past mistakes.

''We aim to be first in the market - and stay in the market,'' he said. To get around production problems that have plagued other projects, Mr. Sinclair has contracted with Timex to produce both the minitelevisions and advanced microcomputers at the big watchmaker's Dundee, Scotland, plant. Marketing is expected to begin by the middle of next year. To avoid getting caught in the price trap again, he plans to sell the mini-televisions for just $100 or so. (An earlier model, announced in 1977, would have cost about $300.) Offices to direct promotion and sales (all mail order) have been opened in Boston, Munich and Paris. Mr. Sinclair, the son of a small London businessman who now works for him, quit school at the age of 17 to engage in several entrepreneurial fits and starts - running a small publishing company, making transistor radio kits and writing for a technical magazine. He set up Sinclair Radionics when he was 22, to assemble components for transistor radios and hi-fi's.

Now 40, he firmly believes he will join the ranks of inventorsturned-entrepreneurs - like Edwin Land, inventor of the Polaroid instant camera -who prove capable of surviving in a world of high technology dominated by multinational companies with million-dollar research budgets. First, however, he must put behind him a track record that has won him a lot of critics. Part of the problem is his own personality. Soon after introducing his hand-held calculator in 1972, for example, (the Executive cost the equivalent of $174 in 1972 and only performed five basic arithmetic functions) Mr. Sinclair began design work on his pet project, the pocket television, while at the same time throwing his small company behind the Black Watch, a digital wrist watch. ''Clive gets ideas so fast that sometimes he does the last thing he thinks up before he finishes with the first,'' explained one electronics expert who has watched Mr. Sinclair's roller-coaster career. ''Clive is not particularly prepared to listen to other people's ideas,'' added a former colleague, Christopher Curry, who has gone on his own to start the micro-computer company, Acorn.

''He is, in a word, irascible.'' Production of the Black Watch was held up for 18 important months because of problems with the supply of components. It finally began in 1975, but quietly died without a recouping of the initial investment. Sinclair Radionics had never become truly large - the company had sales of some $20 million in its best year - and by l976, Mr. Sinclair was forced to seek outside financing in order to continue work on the pocket television. He turned first to the City, London's financial community, but he found no takers. So the National Enterprise Board, a Governmentfinanced organization designed to provide financing for high-risk ventures, bailed out the failing company. But Mr. Sinclair's highly individual style did not mix well with state capitalism. In 1979, Mr. Sinclair left, with a $22,000 ''golden handshake,'' his design team, and his ideas. The N.E.B. wrote off the venture as a $17 million loss. The financial community watched, with a note of self-congratulation. However, Mr.

Sinclair promptly sold his house and his car (a collector's Rolls-Royce), set up Sinclair Research and began production of the ZX8O, an inexpensive, $199.95 microcomputer. He also managed to continue the Government connection with a $1 million grant from the state-controlled National Research and Development Corporation for development of the pocket television, in return for an undisclosed royalty. The lesson from the calculator battle did not go unheeded: ''We want to remain cheap enough to discourage Oriental competition,'' said Mr. Sinclair. ''There is, of course, always the problem in consumer electronics of being overtaken by cheaper products -we are making every effort to update our products.'' With that in mind, Sinclair recently announced the ZX81 (with four microchips compared with 22 in the earlier model) to go into production at Dundee this spring and be priced at retail for about $120. The newer model can also be hooked into a printer, for an additional $112. Mr. Sinclair is now producing 10,000 ZX80's a month, which puts him third in volume of personal computers, behind Apple and Tandy Radio Shack.

His models, which rely on conventional television sets for their screens and cassette recorders to store the programs, are slower, have less memory, can handle far fewer commands and do less complex calculations than those of Apple and Tandy. That difference is, of course, reflected in price. A basic Apple model runs to more than $1,500. Mr. Sinclair is aiming at the novice who wants to learn his way around a computer rather than the small-business executive who wants storage and information processing capacity. ''The Sinclair model has gadget appeal,'' said Gavin Embry, an electronics consultant. ''I have two, one to play with and one to take apart to see how it works.'' More than 50,000 ZX80's were sold in the first nine months of last year, more than half of them abroad, bringing the company $1.8 million in profits on $7 million in revenues. Mr. Sinclair says that he will soon be selling more units than either Apple or Tandy. And, typically, he has his eye on bigger things even than pocket television. ''We have already started a detailed design of an electric car,'' said Mr. Sinclair.

''Yes, I realize that General Motors is working on the same thing, but I'm not particularly nervous about that - and I'm sure that they are not very nervous about me, either. It's a case of mutual lack of nervousness.'' Illustrations: Photo of Clive Sinclair BBC NEWS | UK | Magazine | Faces of the week Printable version Faces of the week Our regular look at some of the faces which have made the news this week. Above are Sir Clive Sinclair, with Bishop Gene Robinson, Jennifer Lopez, Don Estelle, and Tom Kelly Click for more SIR CLIVE SINCLAIR Eighteen years after his C5 electric tricycle failed to revolutionise the transport habits of city dwellers, Sir Clive Sinclair is at it again. He has announced that he is working on a new form of personal transporter. Why are we sceptical? It doesn't take a genius to work out that Sir Clive Sinclair has an image problem, despite the fact that the man himself is, officially, a genius. He has an IQ of 159 and used to chair the egg-heads' club, Mensa.

For Sir Clive, now 63, encapsulates the fortunes of British industry over recent decades; high marks for innovation, low marks for marketing. He is the brilliant lateral thinker whose inventions, at one time, dominated the UK home-computer market. He is the inventor who took on the might of the Japanese and American electronics industry and failed gloriously. The ill-fated C5 On the other hand, his C5 made him a laughing-stock, and his ill-fated romances with glamorous women half his age has only reinforced this reputation. His acumen for invention began in his teens. Before taking his A levels, he designed his first micro-radio. At 17, he became a technical journalist on Practical Wireless and, within a year, had become its editor. By the early 1970s, he had invented the world's smallest amplifier, the Executive pocket calculator and the digital Black Watch. He secured his personal fortune with the first low-priced home computers, the Sinclair ZX80, ZX81 and the Spectrum. In 1983, he became Young Businessman of the Year and received his knighthood. But young British companies like Sinclair and Acorn lacked the entrepreneurial skills of the Americans and Japanese.

What's more, the IBM computer system became the dominant format and embracing it ran counter to the British innovation culture. PR disaster Only Amstrad took it on. Only Amstrad survived. The C5 was not only a product failure, but a public relations disaster. The electric tricycle was deemed unsafe by the Automobile Association because it was too low; lorries couldn't see it. Key to Sir Clive's fortune - the mega selling Spectrum computer One wondered what sort of mind could develop, over several years, something so obviously naff. So his next inventions, namely a battery-powered bicycle engine called a Zeta and the more advanced Zike, met existing market resistance. Production of the Zike ceased after six months. It was a risky adventure that, once again, just failed to come off. Risks were not confined to his working life, it seems. His wife discovered he was playing away and divorced him on the grounds of adultery in 1985. His name subsequently became linked with a host of attractive women less than half his age. In 1989, Mensa member, Bernadette Tynan, 21, accepted his marriage proposal but later changed her mind.

Tabloid fodder He was soon dating a string of young women, and raised eyebrows when he moved a 21 year-old lapdancer, Angie Bowness, into his luxury penthouse apartment. When they parted, she sold her story to the tabloids. Another battery-aided bike, the Zeta So too did 27-year-old Vicky Lee, whose tale in the News of the World prompted the memorable headline, "Sir Clive liked boffin me C5 times a night". Sir Clive is keeping his cards very close to his chest over his new invention. The suggestions are that it might be some kind of enhanced pedestrian transport. "I think Sir Clive Sinclair is certainly capable of pulling one more rabbit out of the hat," says broadcaster and gadget buff, Adam Hart-Davis. "But bike technology, if that is what the new invention is, is not easy to break into. He could be barking up the wrong pavement." Or some might say, just barking. BISHOP GENE ROBINSON Gene Robinson became the first elected openly gay bishop in the worldwide Anglican Church this week. Good news for him; not so for the Church as a whole, perhaps.

The issue has split the Anglican community and 20 dissenting bishops walked out. The Archbishop of Canterbury, Rowan Williams, admitted "there will be difficult days ahead". Gene Robinson offered this prayer. "Before too very long, other denominations will follow and welcome openly gay and lesbian people." Full story JENNIFER LOPEZ Jennifer Lopez has had better weeks. First, her latest film, Gigli, in which she stars opposite fiancï¿½ Ben Affleck, got slated. "Surely no movie could be that bad," was one comment. Then she discovered Affleck had been enjoying a fling in bed with a stripper and three lapdancers he'd picked up in a Vancouver nightclub. The comment by his previous fiancï¿½e, Gwyneth Paltrow, that Affleck's "ideal woman would be a stripper with a Budweiser in each hand", seems to have lost any whiff of sour grapes Vintage Sinclair Vintage Sinclair Contact Vintage Sinclair products from the 1970s and 1980s This site shows some of the products of the inventor and entrepreneur Sir Clive Sinclair, from 1972 to 1985.

Through his companies - Sinclair Radionics, Science Of Cambridge and Sinclair Research, Sir Clive developed some of the earliest pocket calculators, digital watches and most notably in 1980, one of the first complete home computers, the ZX80. Some of his products - Sinclair Research Ltd Tracing the History of the Computer - Sinclair Research Ltd Sinclair Research Ltd is a consumer electronics company founded by Sir Clive Sinclair in Cambridge, England (originally as Sinclair Radionics in 1961) to sell hi-fi equipment, calculators, radios and other products. In 1966 Sinclair created but never sold the world's first pocket television. In 1972 they marketed the world's first pocket calculator, the Sinclair Executive. In the 1980s Sinclair entered the personal computer market with the ZX80 at £99.95, at the time the cheapest personal computer for sale in the UK. In 1982 the ZX Spectrum was released, later becoming Britain's best selling computer, competing aggressively against Commodore and Amstrad.

The combination of the 1984 failures of the Sinclair QL computer and TV80, and the 1985 Sinclair C5 electric vehicle bankrupted the company, and a year later Sinclair's products were sold to Amstrad. Sinclair still exists today, continuing to market Sir Clive Sinclair's newest inventions. The first twenty years: 1961 to 1980 Sinclair Radionics On 25 July 1961 Sir Clive Sinclair founded Sinclair Radionics in Cambridge, England after raising funds to start the business by writing articles for Practical Wireless magazine. Sinclair Radionics developed hi-fi products, radios, calculators and scientific instruments. In 1963, Sinclair Radionics introduced their first radio with the "Sinclair Slimline" in kit form at forty-nine shillings and sixpence. A year later in 1964 Sinclair released the "Micro-6", match-box size radio which the company claimed was the "world's smallest radio". It could also be worn on your wrist with the "Transrista".

In 1965 the "Micro-FM" debuted as "the world"s first pocket-size FM tuner-receiver", but was unsuccessful due to technical difficulties. Despite problems, illegal clones were produced in the far-east. Sinclair's final 1960s radio kit was the 1967 "Micromatic", it was billed as "the world's smallest radio" like Sinclair's earlier radios. The "Micromatic" was a reasonable success and was sold until 1971. In May 1971 Sinclair Radionics made £85,000 profit on £563,000 turnover; the following year profit increased to £97,000 on turnover of £761,000. In 1966 Sinclair Radionics entered the hi-fi market with the "Stereo 25", a low-cost pre-amp control system, production was halted in 1968 due to low supply of transistors which had been purchased in 1964 as rejects from other manufacturers.

In 1969 it was replaced by the "Stereo Sixty", which soon became Sinclair's most successful audio product, being the second product of the "Project 60" range. The "Project 60" products sold well and were supplemented by the "Project 605" kit in 1972. It was eventually superseded by the more advanced "Project 80" kit in 1974. In September 1973 Sinclair purchased "Ablesdeal" so that he would be able to avoid the delay of incorporating a company if it became convenient for him to shift his ambitions away from Sinclair Radionics. In May 1973 Sinclair Radionics generated £1.8m turnover. In 1966, Sinclair Radionics developed the world's first portable television, the "Microvision", but never attempted to sell it because development costs would have been too high based on the complicated design the Microvision used. In 1976 it was sold as a revised version, the "Microvision TV1A/MON1A" at £99.95.

Supply exceeded demand, and 12,000 units were left unsold until they were sold off cheaply. This resulted in a £480,000 loss for Sinclair. Sir Clive Sinclair was certain that the TV1B model released in 1978 would be more successful, but sales were disappointing. The technology was sold to Binatone. During the majority of the 1970s Sinclair focused on building the most affordable pocket calculators, with the best design. In 1972, Sinclair released the world's first slim-line pocket calculator, the Sinclair Executive, for £79.95. The calculator only included basic math functions, and the LED display required lots of power. It is often credited as being the world's first attractively-styled calculator, that didn't require mains power to be used like prior calculators. The executive was a phenomenal success, earning Sinclair £1.8m in profit. In 1973 the "Executive Memory" was introduced at a far cheaper price of £24.95. In 1975 Sinclair Radionics released the Sinclair Scientific, a scientific pocket calculator for £99.95.

It used RPN, and displays only in 5 digit mantissa or 2 digit. In 1977 a revised model, the "Scientific Programmable", was released at £29.95. The Scientific Programmable Mark 2 was later released, reducing the price to £17.22. Sinclair attempted to capture the top-end calculator market with the Sinclair Sovereign, available in plated gold or silver, it was critically acclaimed for its excellent engineering and design and enjoyed short success. In August of 1975 Sinclair introduced the Black Watch at £17.95 in kit form and £24.95 ready-built. Including a 5-digit LED display, it suffered from technical flaws related with the battery and accuracy. The company began to see significant commercial losses because of the product. In August 1975, Sinclair changed the name of Ablesdeal to "Sinclair Instrument Ltd". Exactly a year later the National Enterprise Board bought a 43% stake in Sinclair Radionics for £650,000.

Finding it inconvenient to share control of his company, Sinclair encouraged Chris Curry, who had been working for Radionics since 1966, to leave and get Sinclair Instrument started. Sinclair Instrument developed the "Wrist Calculator" to generate cash, it soon became a commercial success selling in surprising figures. In July 1977 Sinclair Instrument Ltd was renamed to "Science of Cambridge Ltd". Around about the same time, Ian Williamson showed Chris Curry a prototype computer based around a National Semiconductor SC/MP and some parts taken from an earlier Sinclair calculator. Curry was impressed and encouraged Sinclair to adopt this as a product; an agreement was reached with Williamson but no contract was ever signed, Nat Semi had offered to redesign the project so that it used only their components and they also offered to manufacture the boards. Science of Cambridge In June 1978 Science of Cambridge launched a microcomputer kit, marketed as the MK14, based around the National SC/MP chip. By July 1978, a personal computer project was already underway. When Sinclair learnt that the NewBrain could not be sold at below the sub-£100 price that he envisaged, his thoughts turned to the ZX80 instead.

In May 1979 Jim Westwood started the ZX80 project at Science of Cambridge, it was launched in February 1980 at £79.95 in kit form and £99.95 ready-built. In November Science of Cambridge was renamed to "Sinclair Computers Ltd". Success and then decline: 1981 to 1986 In March 1981 "Sinclair Computers" was renamed to "Sinclair Research Ltd" and the Sinclair ZX81 was launched at £49.95 in kit form and £69.95 ready-built, by mail order. In February 1982 Timex obtained a license to manufacture and market Sinclair's computers in the USA under the name Timex Sinclair. In April the ZX Spectrum was launched, priced at £125 for the 16 kB RAM version and £175 for the 48 kB version. In July Timex launched the TS 1000 (a version of the ZX81) in the US.

In March 1982 Sinclair made an £8.55m profit on turnover of £27.17m, including £383,000 government grants for flat screen. In 1982 Clive Sinclair converted the Barker & Wadsworth mineral water bottling factory at 25 Willis Road, Cambridge into the Sinclair Building to use it as the company's new headquarters. (It was sold to Cambridgeshire County Council in December 1985 due to Sinclair's immense debts and finance troubles.) In January 1983 the ZX Spectrum personal computer was presented at the Las Vegas Consumer Electronics Show. In September the Sinclair TV80 television was launched, using flat-screen technology unlike Sinclair's previous CRT televisions, the TV80 was a commercial failure only selling 15,000 units and not covering its development costs of £4m. In late 1983, Timex decided to pull out of the "Timex Sinclair" venture, which had failed to break the US market as expected due to strong competition. However Timex computers continued to be produced for several years in other countries.

Timex Portugal, with the TS 2048 and 2068, launched improved versions capable of displaying more colours, and a better circuit design. They also developed and launched the FDD 3000, a floppy disk system, that was not well received by the market. The Sinclair QL was announced on January 12, 1984, shortly before the Apple Macintosh actually went on sale. This was a new computer, to be aimed at the business market and costing £399. However, at this point the final design had not yet been completed. Shipping finally started in May, with 13,000 orders taken, but only a few hundred units delivered at first. Because the initially supplied ROM had proved insufficient, early machines were shipped with a "kludge" hanging out of the machine with additional ROM space. Your Sinclair noted that it was "difficult to find a good word for Sinclair Research in the computer press". Fully working QLs were not available until late summer; complaints against Sinclair regarding delays were upheld by the Advertising Standards Authority in May of the year (in 1982 it had upheld complaints about delays in shipping Spectrums).

Especially severe were allegations that it was cashing cheques months before machines were shipped. The QL was nowhere near as successful as Sinclair's earlier computers. In the autumn, Sinclair were still publically predicting it would be a "million seller", with 250,000 sold by the end of the year. QL production was suspended in February 1985, and the price was halved by the end of the year. Between 1981 and 1988 Sinclair created ten peripherals for their computers, including joysticks, a printer, hard drive, and memory expansion modules. Some of the peripherals were developed by other companies but still marketed under the Sinclair brand. External storage for the Spectrum was usually on tapes, as was common in the era. Rather than an optional disk drive, Sinclair instead opted to offer their own system, the ZX Microdrive, a tape-loop cartridge system that was rather unreliable. This was the primary storage option for the QL as well. The "ZX Spectrum+", a retooled ZX Spectrum with a plastic keyboard, was launched in October and appeared on WHSmith's shelves the day after release.

Retailers stocked the machine in large numbers in expectation of good Christmas sales, however it did not sell in the numbers expected and, because retailers still had unsold stock, Sinclair's income from orders dipped alarmingly in January. The Spectrum+ had the same technical specifications as the original Spectrum. An upgraded Spectrum, the ZX Spectrum 128, was launched in Spain in September 1985, by the Spanish firm Investronica. January 1986 saw the machine launched in the UK, apparently in an attempt to generate cash. Trouble and Amstrad acquisition In January 1985, Sinclair released the "FM Wristwatch Radio", an LCD wristwatch with a radio attached. The aerial was built into the strap and the battery was hidden in the clasp, presumably in an attempt to balance out the considerable weight of the watch. The watch had several usage problems, and never went into full production, making it one of the rarest Sinclair products. Sir Clive had long held an interest in electric vehicles and during the early 1980s worked on the design of a single-seater "personal vehicle".

A new company, Sinclair Vehicles Ltd, was formed in March 1983 (allowing Sinclair Research to concentrate on electronics) and its Sinclair C5 electric vehicle was launched on 10 January 1985. The battery powered vehicle aimed to solve environmental problems and be the first truly affordable vehicle at £399. It was a commercial disaster, selling only 17,000 units and losing Sinclair £7m, Sinclair Vehicles going into liquidation later the same year. The C5, combined with the failures of the QL and the TV80, caused investors to lose confidence in Sir Clive. On 28 May 1985, Sinclair had announced that it wanted to raise an extra £10m to £15m to restructure Sinclair Research. Given the loss of confidence in the company, this proved hard to find. In 1986, the company sold its entire computer product range and the "Sinclair" brand name to Amstrad. This deal did not involve the company, merely its name and products.

The tireless inventor: 1990s to present Today the company still exists, but in a completely different form than it did in the 1980s. In 1993, 1994 and 1995 Sinclair made continuing losses on decreasing turnover, and began to worry investors since Clive Sinclair himself was using his own personal wealth to fund his inventions. By 1990 Sinclair's entire staff had been reduced to Sinclair himself, a salesperson/administrator, and R&D employee. By 1997 reportedly only Sinclair on his own was working at his company. In 1992 the "Zike" electric bicycle was released, Sinclair's second attempt at changing means of transportation. The "Zike" was a commercial failure much like the C5 was, and only sold a total of 2,000 units. It had a maximum speed of 10 mph (16 km/h), and was only available through mail order. In 1997 Sinclair released the world's smallest radio with the "Z1 Micro AM Radio".

In 2003, the Sinclair "ZA20 Wheelchair Drive Unit" was introduced, designed and manufactured in conjunction with Hong Kong's Daka Designs, a partnership which also led to the SeaDoo Sea Scooter, an underwater propulsion unit. Sinclair recently announced that they will release a folding bicycle, named the A-Bike, in 2005.

Question: The Executive calculator and the Black Watch were products from which inventor?
Answer: CLIVE SINCLAIR